A wide-angle Head-Up display with three-component combiner providing imaging of graphic information of various type in optical infinity intended for piloting and performance of various tasks in aircrafts, helicopters, cars and other operated objects is proposed. Head-Up display, further indicated HUD, consists of two basic parts: a display module generating an original informational image of high brightness and an optical system projecting the original image to optical infinity against an outer space background in the direction of view of an operator. Such optical system is known as collimating optical system and the image formed by this system is known as collimated image. Being a part of the collimating optical system a semitransparent combiner is used to combine the luminous collimated image with outer space.
It is known that full and instantaneous fields of view are the main characteristics of the collimating optical system of HUD. Full field of view specifies maximum size of information field which the operator can view against the outer space background taking into account additional movements of his head within an eyes box. The instantaneous field of view is a part of full field of view seen by the operator while his head is located in fixed position in a center of the eyes box. The higher these angular parameters value the more informational capabilities HUD has that is of the utmost importance for performance of some tasks. At the same time discomfort caused by need to move the head horizontally and vertically, especially under accelerative forces, in order to read visual information located in peripheral areas of full field of view is eliminated due to increasing of size of the instantaneous field of view.
Currently two methods are used to build the collimating optical system for HUD:                ax symmetric scheme using lens optics; and        plane-symmetric scheme using decentered no planar reflecting elements mainly being holographic optical elements—HOE.        
The design feature of the ax symmetric collimating optical system is: to enlarge full angular field of view, it is necessary to reduce a focal length and to enlarge instantaneous angular field of view, it is necessary to increase a light diameter of an output lens. So it is necessary to increase a relative aperture by increasing a diameter of output lens of optical system in order to increase full and instantaneous angular fields of view simultaneously. But always there are design constraints excluding uncontrolled increasing of the diameter of output lens. Substantially this is to ensure safety for the operator since the distance from the operator to display is reduced. Therefore generally collimating optical systems are used having the diameter of the output lens of 120-140 mm, full angular field of view (circular) not exceeding 25° and instantaneous field of view 16° in horizontal direction and 12° in vertical direction and using single flat semitransparent reflector—single-component combiner, installed above the output lens and shifted by 40°-50° relative to the horizontal plane. Significant moving of head the operator in horizontal and vertical directions is required while reading information, formed by HUD within full angular field of view. Devices by U.S. Pat. No. 6,392,812, U.S. Pat. No. 7,391,574, U.S. Pat. No. 8,879,156 are examples of HUD of this type.
The HUDs are known with ax symmetric collimating optical system using two parallel plane semitransparent reflectors installed above the output lens—two-component combiner—providing increasing of the instantaneous field of view up to 17°×17° (patent US 2012/0127381 A1). Considered configurations of HUDs of most usual type based on ax symmetric collimating optical system have sufficiently restricted technical capabilities for simultaneous increasing of full and instantaneous angular fields of view.
Application of plane-symmetric scheme using decentered no planar reflecting elements mainly being holographic optical elements—HOE allows to expand full and especially instantaneous angular fields of view of collimating optical system and make closest approach to their equality. Theoretical examples of building of such collimating optical systems of HUD based on HOE may be devices by U.S. Pat. No. 4,407,564 and U.S. Pat. No. 5,640,275. Practical application of HOE in these devices allows to increase size of full angular field of view up to 30° and instantaneous angular field of view up to 27° in horizontal direction and up to 24° and 22° in vertical direction accordingly. In such collimating optical systems single or several HOE installed on the system output are the most complicated and bulky optical elements. At the same time the main HOE is installed in front of the operator and works as semitransparent combiner providing forming of collimated image of information field against the outer space background. The size of such HOE is up to 300-350 mm and usually in itself is a non-planar decentered glass substrate coated with complex multi-layered (or volume) hologram providing high transparency within visible spectral range (up to 80%) and effective reflection (up to 70-80%) for the light rays of specified (operating) wavelength (usually green) coinciding with a maximum radiation of imager (CRT or LCD) generating primary image. To make such HOE sophisticated technology providing high vibration strength and seismic stability is required that is accessible only for highly developed industrial production and costly. For this reason only limited number of up-to-date aircrafts possessing high tactical and technical capabilities is equipped with HUD provided with collimating optical systems based on HOE.
A method of widening of angular field of view of HUD in horizontal plane is disclosed in a U.S. Pat. No. 8,982,472. The suggested method does not provide capability to increase angular field of view in vertical plane additionally. Meanwhile the increasing of the field of view in vertical direction is of the utmost importance for performance of tactical tasks in an upper hemisphere. In present Application for patent a complex solution of the problem of increasing of full and instantaneous fields of view in the directions of both coordinates by using ax symmetric schemes with application of lens optical elements and flat reflectors is disclosed. The ideas disclosed in the U.S. Pat. No. 8,982,472 have been developed further in the present Application. To solve the problem of increasing of angular field of view of HUD an integral approach to the problem solving has been used that made it possible to gain presumable result.